JP2015056818A - Imaging apparatus and stereo camera using imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve adjustment accuracy and reduce factors of a secular change after adjustment, in the positional adjustment of an imaging device in a manufacturing process.SOLUTION: An imaging apparatus comprises: an imaging device 4; a circuit board 8 with the imaging device 4 mounted thereon; a lens 1; a casing 6 connected with the circuit board 8; a circuit board fixing plate 7 provided between the circuit board 8 and the casing 6; plural screws 5 for fixing the circuit board 8 and the casing 6, or the circuit board fixing plate 7 and the casing 6; and a special washer 3 provided between the head of at least one of the screws 5 and the casing 6. The special washer 3 is so shaped as to be in contact with a wall of the casing 6, at its one side.

Description

  The present invention relates to an imaging device on which an imaging element is mounted, and a stereo camera using the imaging device.

  A stereo camera that calculates the distance to an object using a pair of images captured by two imaging means and recognizes the object, thereby providing an in-vehicle system and a suspicious person that supports safe driving of the car It has begun to be applied to monitoring systems that detect intrusions and abnormalities.

  The principle of stereo image processing used in these systems is to obtain a distance by applying a triangulation technique to a pair of captured images that are imaged at a position apart from each other. The apparatus generally includes a pair of imaging units and a stereo image processing LSI that performs triangulation processing on a pair of captured images output by these imaging units.

Because of the above principle, it is ideal that there is no deviation other than parallax between a pair of images, and for each imaging means, adjustment is performed with high accuracy so that there is no deviation in optical characteristics and signal characteristics, A structure that can maintain the accuracy is required.
Patent Document 1 discloses a structure for adjusting the relative positional relationship between a pair of imaging elements in such a stereo camera. Here, in a camera assembly structure having a camera body part and an optical system built in the camera body part, the camera is attached to the camera body part, and optical information via the optical system is converted into electrical information. A circuit board on which a sensor to be converted is mounted; a first state in which the circuit board is fixed to the camera body; and a second state in which the mounting position of the circuit board in the camera body can be displaced. And a mounting screw that can be used.

Japanese Patent Laid-Open No. 2001-242521

  In the stereo camera, in order to improve the measurement accuracy as described above, it is necessary to adjust the relative positions of the left and right imaging units with high accuracy. Another problem is that a shift occurs when the adjusted position is fixed.

  In Patent Document 1, an adjustment jig for adjusting the attachment position of the attachment member is attached to the holding portion in which a space for housing the attachment member is formed, and the holding portion, and inside the holding portion. A first urging means for urging the stored attachment member in the horizontal direction, and attached to the holding portion, and holding the attachment member together with the first urging means, and adjusting the horizontal position of the attachment member. A first adjusting means; a second urging means attached to the holding part and urging the attachment member in a vertical direction; and an attachment member attached to the holding part and together with the second urging means. The apparatus includes a second adjustment unit that sandwiches and adjusts the vertical position of the attachment member, and is a strong adjustment device.

  However, because of the means for fixing the circuit board with the image pickup device with the screw, the rotation of the screw is transmitted to the circuit board by the frictional force between the seat surface of the screw and the surface of the circuit board, but the circuit board is firmly held. Therefore, the circuit board is distorted, which includes the possibility of positional displacement after the adjustment jig is removed or due to internal distortion over time.

  An object of the present invention is to improve the accuracy of adjustment of the position of an image sensor in the production process and to reduce the factors of change with time after adjustment.

  In order to solve the above problems, an imaging device of the present invention is provided with an imaging element, a circuit board on which the imaging element is mounted, a lens, a casing connected to the circuit board, and a circuit board and the casing. A fixing plate, a circuit board and a housing, or a plurality of fixing members for fixing the fixing plate and the housing, and a rotation suppressing member provided between the head and the housing of at least one fixing member of the plurality of fixing members, The rotation restraining member is configured to have a shape that comes into contact with the wall of the housing at the side.

  In addition, the stereo camera of the present invention includes a first imaging device, a first circuit board on which the first imaging device is mounted, a first lens, a first imaging unit, and a second imaging. An element, a second circuit board on which a second imaging element is mounted, a second lens, a second imaging unit, a first imaging unit at one end, and a second at the other end. A housing provided with an imaging unit, a first fixing board provided between the first circuit board and the housing, a second fixing board provided between the second circuit board and the housing, and a first A first plurality of fixing members for fixing the circuit board and the housing, or the first fixing plate and the housing, and a second circuit board and the housing, or a second fixing plate and the housing for fixing the housing. A plurality of fixing members, a first rotation suppressing member provided between the head and the housing of at least one first fixing member of the first plurality of fixing members, and a second plurality of fixing members A second rotation restraining member provided between the head of at least one second fixing member and the housing, wherein the first rotation restraining member and the second rotation restraining member are wall portions of the housing. It is set as the structure which has a shape which contacts in side.

  ADVANTAGE OF THE INVENTION According to this invention, in the position adjustment of the image pick-up element of a production process, while adjusting accuracy, the element of the time-dependent change after adjustment can be decreased.

It is a figure which shows the structural example of the one imaging part of the stereo camera which concerns on this invention. It is a figure which shows the housing structure example of the stereo camera which concerns on this invention. It is a figure which shows one structural example to which the one imaging part of FIG. 2 was expanded. It is a figure explaining the suppression method of the movement of the circuit board fixing plate of the imaging part of this invention. It is a figure which shows an example of the adjustment jig of the stereo camera which concerns on this invention. It is a figure explaining the adjustment method using the chart of the stereo camera of this invention. It is a figure explaining the relative relationship of the lens and imaging device in the adjustment method of this invention. It is a figure which shows an example using the special washer for the imaging part of this invention. It is a figure which shows the other example which used the special washer for the imaging part of this invention. It is a figure which shows the other structural example of the one image pick-up part of the stereo camera which concerns on this invention. It is a figure explaining the direction which tightens the screw in the image pick-up part of the present invention. It is a figure explaining the difference with the case where there is no special washer of this invention, and a case. It is a figure explaining an example of the connection of the circuit board plate of this invention.

  Each embodiment will be described below with reference to the drawings.

  FIG. 2 is a diagram showing an example of the housing structure of the whole image of the stereo camera according to the present invention.

  A stereo camera that is an imaging device is a device that includes two imaging units at the end of the housing 6, and a lens that is an optical unit and an imaging element that is an imaging unit are arranged in the imaging unit. The two images captured by the image sensors in the imaging units at both ends have a shift due to parallax, and based on this, a triangulation technique is applied by a signal processing circuit in which the distance of the object is placed inside the housing 6. The distance is calculated, and the calculated direction and distance of the target are output.

  Next, in order to explain the inside of the imaging unit of the stereo camera of the present invention, FIG. 3 shows an enlarged view seen from the direction A of FIG. In the product state, the enlarged portion is covered with a cover, but the cover is omitted to explain the present invention.

  In the housing 6, a circuit board 8 on which an imaging element 4 as an imaging means is mounted and a circuit board fixing plate 7 as a fixing plate are fixed with screws 5 as fixing members. 7 is fixed to the housing 6 with a screw 5 as a fixing member via a washer as a rotation suppressing member, here a special washer 3. In this embodiment, a spacer 2 that is an adjustment member capable of adjusting the height is provided between the housing 6 and the circuit board fixing plate 7.

  Note that a plurality of screws 5 as fixing members are used to fix the circuit board 8 and the casing 6 or the circuit board fixing plate 7 and the casing 6 as a fixing plate, and a plurality of screws 5 are provided in one imaging unit.

  The image sensor 4 is disposed in a portion corresponding to the back surface of the lens 1 in FIG.

  Next, in order to explain the arrangement of the components described in FIG. 2 and the function of the present invention, a cross-sectional view of one imaging unit of the stereo camera shown in FIG. 1 is used.

  The lens 1 is fixed to the housing 6. The lens 1 has a mechanism for adjusting the distance from the image sensor 4 in order to focus. In the present embodiment, the screw 5 is formed on the outer periphery of the lens 1 on the image pickup device 4 side, the screw 5 is formed on the corresponding inner diameter of the housing 6 of the stereo camera, and the lens 1 is rotated, whereby the image pickup device is obtained. The distance can be adjusted in the vertical direction of the image pickup surface 4.

  The imaging device 4 is mounted on the circuit board 8 with the imaging surface disposed on the lens 1 side and an electrical connection portion on the opposite surface. Although omitted in FIG. 1, as described in FIG. 3, the circuit board 8 is fixed to the circuit board fixing plate 7 using screws 5 or the like.

  The circuit board fixing plate 7 has a through hole and is fixed to the housing 6 through screws 5 which are a plurality of fixing members.

  Since the diameter of the through hole of the circuit board fixing plate 7 is larger than the diameter of the screw 5, the circuit board fixing plate 7 adjusts the relative position of the imaging element 4 with respect to the lens 1 within the range of the diameter difference with respect to the mounting surface. It has a possible structure.

  The image sensor with respect to the lens 1 is adjusted to a desired position and then fixed with a screw 5. It fixes to the housing | casing 6 through the special washer 3 which is a rotation suppression member so that it may distribute | arrange between the seat surface of the screw 5, and the circuit board fixing plate 7. FIG.

  The special washer 3 has a shape that comes into contact with the wall of the housing 6 at the side, and does not rotate on the installation surface.

  In this embodiment, as shown in FIG. 3, the screw 5 is provided at three places, but one or a plurality of special washers can be inserted.

  Next, the adjustment process and the fixing process of the relative position of the image sensor 4 will be described, and the function of the special washer 3 will be described.

  As a method of adjustment, a chart 12 as shown in FIG. 6 is used. On the chart 12, a pattern showing a pair of optical axis centers 13 is drawn at the same interval as the lens interval (base line length) at the left and right ends of the stereo camera. The stereo camera is arranged so that the optical axes of the left and right lenses overlap vertically on the left and right optical axis centers 13 of the chart 12. At this time, the relative relationship among the optical axis center 13, the lens 1, and the image sensor 4 is linearly arranged as shown in FIG. 7.

  The position adjustment of the image sensor 4 is performed by adjusting the pixel position of the optical axis center 13 reflected in the image from the image obtained by imaging the optical axis center 13 with the image sensor 4 through the lens 1 and the pixel position where the optical axis center 13 is to be matched. The circuit board fixing plate 7 is moved along the mating surface with the housing 6 in such a direction that the difference is eliminated.

  FIG. 5 illustrates an adjustment jig used for performing the operation described above.

  A cutout is formed in the circuit board fixing plate 7. The adjustment jig 10 includes a pin having a shape that is in close contact with the notch, and the pin can hold the circuit board fixing plate 7 by pressing the adjustment jig 11.

  The adjustment jig 10 can be moved on the same surface as the circuit board fixing plate 7 by being mounted on an actuator that is moved by an instruction from a personal computer or the like. Thereby, as described above, the image obtained from the image sensor 4 is taken into the personal computer, and the actuator is moved by the difference between the array position of the optical axis center 13 on the image and the target array position, thereby obtaining the target array position. Automatic adjustment can be possible.

  As described above, the position of the image pickup device 4 is adjusted using the adjustment jig 10 holding the circuit board fixing plate 7, and then the screw 5 is tightened and fixed in a state where the position of the adjustment jig 10 is held. . After the adjustment, the screw 5 is tightened and fixed. The mechanism of the present invention at that time will be described with reference to FIG.

  FIG. 12A shows the case of the present invention with a special washer, and FIG. 12B shows the case without a special washer.

  In the case of FIG. 12 (b), when rotating to tighten the screw 5, the circuit board fixing plate 7 is shifted in the rotation direction due to friction between the seating surface of the screw 5 and the circuit board fixing plate 7. For this reason, the position of the adjusted image sensor 4 is shifted. In the case of FIG. 12A, the contact force between the seat surface of the screw 5 and the special washer 3 receives frictional force on the circuit board fixing plate 7 due to friction, but the special washer 3 is in contact with the housing 6 at the side. Therefore, the shift in the rotation direction is suppressed. As described above, since the circuit board fixing plate 7 is in contact with only the special washer 3, the shift in the rotation direction due to the rotation of the screw 5 is suppressed, and the shift of the image sensor 4 is suppressed.

  In the embodiment described so far, the case of using three screws 5 is used. However, the special washer 3 can be inserted at one place or a plurality of places with respect to the position of the screw 5. In the case of one place, first tighten the screw 5 into which the special washer 3 is inserted. Then, it is set as the procedure which tightens the other screw 5. FIG.

  Further, in the structure of FIGS. 1 and 3 shown for explaining the present embodiment, a spacer 2 that is an adjustment member capable of adjusting the height between the circuit board fixing plate 7 and the housing 6 of the stereo camera. Is inserted through the screw 5.

  It is necessary to arrange the optical axis of the lens 1 in the vertical direction of the imaging surface of the imaging device 4 in FIG. 1, and the imaging device 4 is solder-mounted on the circuit board 8 in the form of BGA or the like. However, the vertical direction of the image sensor 4 may deviate from the optical axis direction of the lens 1 due to the inclination when the image sensor 4 is mounted and the height variation of the BGA. The spacer 2 having a different height is prepared, and the height of the spacer 2 to be inserted can be selected and corrected according to the direction of deviation from the optical axis direction. That is, the inclination of the imaging surface of the imaging device 4 with respect to the lens 1 can be adjusted by providing the spacer 2 that is an adjustment member.

  However, as shown in FIG. 10, the circuit board 8 and the case 6 of the stereo camera may be connected with a certain height without providing the spacer 2. Further, as shown in FIG. 13, the height of one of the three locations on the circuit board fixing plate 7 is fixed, and the inclination can be arbitrarily adjusted by changing the height of the two locations.

  In the case of a stereo camera, as described above, two left and right imaging units are arranged, but both the left and right imaging units (the first imaging unit and the second imaging unit) have a housing 6 and sides. A special washer 3 is provided as a rotation restraining member in contact therewith. This naturally suppresses the shift in the rotational direction due to the rotation of the screw 5 and suppresses the shift of the image sensor 4.

  Although the stereo camera having two image sensors has been described so far, the present invention has a similar problem even in an image pickup apparatus having one image sensor. The rotation can be suppressed.

  According to the above configuration, in the position adjustment of the image sensor in the production process, it is possible to improve the adjustment accuracy and to reduce the elements of the change with time after the adjustment. Also, the adjustment device does not require a strong jig and can be realized with low-cost equipment.

  FIG. 4 is an embodiment that suppresses the movement of the circuit board fixing plate 7 different from the first embodiment.

  In the first embodiment, the special washer 3 is in contact with the case 6 of the stereo camera at the side. In this embodiment, the pin 11 is inserted between the special washer 3 and the housing 6 of the stereo camera, the screw 5 is tightened, and then the pin 11 is removed.

  As in the case described with reference to FIGS. 1 and 12, the movement of the circuit board fixing plate 7 can be suppressed by suppressing the movement of the special washer 3.

  FIG. 8 is an embodiment in which the number of special washers 3 of the first embodiment is different, and is an embodiment in which the special washers 3 of the first embodiment are arranged at two locations of the screw 5. That is, the special washer 3 as a rotation restraining member is provided on each of the two screws 5 on the wall side of the housing 6.

  When the special washer 3 is arranged in only one place, after tightening the screw 5 with the special washer 3, the other screws 5 are fastened. The two places can be evenly tightened by arranging them at the two places on the side in contact with.

  FIG. 9 is an embodiment in which the shape of the special washer 3 of the first and third embodiments is different, and is an embodiment in which two parts of the special washer 3 of the third embodiment are arranged as one part. That is, one special washer 3 as a rotation restraining member is provided across the two screws 5 on the wall portion side of the housing 6.

  By using the special washer 3 as one component and increasing the area in contact with the housing 6, not only the size is increased, but also the movement of the circuit board fixing plate 7 when the screw 5 is tightened is further suppressed. Can be handled easily during production.

  FIG. 11 shows an embodiment in which when two special washers 3 are provided as in the embodiment 3, the screw threads are formed so that the screw tightening directions are different at the respective locations.

  In one part, the thread of screw 5-2 tightens clockwise, whereas in the other part, the thread of screw 5-1 tightens counterclockwise. It is possible to cancel the force due to the rotation direction received by the circuit board fixing spacer 7.

This only changes the direction in which the two screws in one imaging unit are tightened. When a stereo camera is used, the two imaging units need to be tightened in the same direction. Specifically, in the first imaging unit, as shown in FIG. 11, when the two screws 5 that are a plurality of fixing members are tightened clockwise and tightened counterclockwise, However, similarly, the two screws 5 are tightened clockwise and tightened counterclockwise. If all the plurality of screws are tightened clockwise in the first imaging unit, all the screws are also tightened clockwise in the second imaging unit, so that the first imaging unit (left imaging unit) and the first imaging unit Even when a shift caused by the rotation of the screw occurs in the second image pickup unit (right image pickup unit), the same shift occurs, and accurate parallax calculation is possible.

DESCRIPTION OF SYMBOLS 1 Lens 2 Spacer 3 Special washer 4 Image sensor 5 Screw 6 Case 7 Circuit board fixing plate 8 Circuit board 10 Adjustment jig 11 Pin 12 Chart 13 Optical axis center

Claims (12)

An image sensor;
A circuit board on which the image sensor is mounted;
A lens,
A housing connected to the circuit board;
A fixing plate provided between the circuit board and the housing;
A plurality of fixing members for fixing the circuit board and the casing, or the fixing plate and the casing;
A rotation suppressing member provided between a head of at least one fixing member of the plurality of fixing members and the housing;
The rotation suppression member is an imaging apparatus having a shape that contacts a wall portion of the housing at a side. The imaging device according to claim 1,
The rotation suppression member is an imaging device that is a washer. The imaging apparatus according to claim 2, wherein
The rotation suppression member is an imaging device provided on each of the two fixing members on the wall side of the housing. The imaging apparatus according to claim 2, wherein
The rotation suppression member is an image pickup apparatus in which one rotation suppression member is provided across the two fixing members on the wall side of the housing. The imaging device according to claim 1,
An imaging apparatus having an adjustment member that is provided between the housing and the fixed plate and adjusts the height. The imaging device according to claim 5.
The adjustment member is a spacer,
The said spacer is an imaging device which adjusts the inclination of the imaging surface of the said image pick-up element with respect to the said lens. The imaging device according to claim 3.
The two fixing members are imaging devices having different fastening directions. The imaging apparatus according to claim 4.
The two fixing members are imaging devices having different fastening directions. A first imaging unit, a first circuit board on which the first imaging device is mounted, a first lens, and a first imaging unit,
A second imaging unit, a second circuit board on which the second imaging device is mounted, a second lens, and a second imaging unit.
A housing provided with the first imaging unit at one end and the second imaging unit at the other end;
A first fixing plate provided between the first circuit board and the housing;
A second fixing plate provided between the second circuit board and the housing;
A plurality of first fixing members that fix the first circuit board and the housing, or the first fixing plate and the housing;
A second plurality of fixing members for fixing the second circuit board and the casing, or the second fixing plate and the casing;
A first rotation suppressing member provided between a head of at least one first fixing member of the first plurality of fixing members and the housing;
A second rotation suppressing member provided between a head of at least one second fixing member of the second plurality of fixing members and the housing;
The first rotation suppression member and the second rotation suppression member are stereo cameras having a shape that comes into contact with a wall portion of the housing at a side. The stereo camera according to claim 9, wherein
The first rotation suppression member and the second rotation suppression member are stereo cameras that are washers. The stereo camera according to claim 9, wherein
The first rotation suppression member is provided on each of the first plurality of fixing members on the wall side of the housing.
The second rotation suppression member is a stereo camera provided on each of the second plurality of fixing members on the wall side of the housing. The stereo camera according to claim 11, wherein
The first plurality of fixing members and the second plurality of fixing members are stereo cameras having the same fastening direction.